Eukaryotic prefoldin (PFD) is a heterohexameric chaperone with a jellyfish-like structure whose function is to deliver nonnative target proteins, principally actins and tubulins, to the eukaryotic cytosolic chaperonin for facilitated folding. Here we demonstrate that functional PFD can spontaneously assemble from its six constituent individual subunits (PFD1-PFD6), each expressed as a recombinant protein. Using engineered forms of PFD assembled in vitro, we show that the tips of the PFD tentacles are required to form binary complexes with authentic target proteins. We show that PFD uses the distal ends of different but overlapping sets of subunits to form stable binary complexes with different target proteins, namely actin and alpha- and beta-tubulin. We also present data that suggest a model for the order of these six subunits within the hexamer. Our data are consistent with the hypothesis that PFD, like the eukaryotic cytosolic chaperonin, has co-evolved specifically to facilitate the folding of its target proteins.

About

SciCrunch is a data sharing and display platform. Anyone can create a custom portal where they can select searchable subsets of hundreds of data sources, brand their web pages and create their community. SciCrunch will push data updates automatically to all portals on a weekly basis. User communities can also add their own data to SciCrunch, however this is not currently a free service.